OH, SHOOT: A fallen Matt Gilroy (left) and goaltender Henrik Lundqvist fail to stop a shot by Olli Jokinen (not pictured) during the Rangers’ 4-3 loss to the Jets last night at the Garden. Photo: Paul J. Bereswill

Desperation propelled the Rangers to a furious, final 20 minutes last night at the Garden. Now the same sense of urgency following a fourth straight defeat must propel the Blueshirts to a consistent 60 minutes a night of similar effort in order to prevent the season from slipping away.

“I don’t see why we can’t play 60 minutes of desperate hockey,” Ryan Callahan, who was immense in every conceivable aspect of last night’s 4-3 defeat to the Jets, told The Post after his team’s slide reached 0-3-1. “We’ve played that way and won that way before, so obviously it can be done.”

Rick Nash might be able to return to the lineup as soon as tomorrow night after missing the last four games (believed concussion-like symptoms) when the Lightning come to the Garden. Michael Del Zotto, who missed his second straight with a lower body issue, could conceivably return then as well, and tomorrow would probably be optimistic for Ryan McDonagh (believed concussion-like symptoms).

A nearly full squad could turn the Blueshirts’ pitcher to half-full from the half-empty 8-8-2 start — well, more stops than starts so far — that includes a 1-3-2 slide over the last half-dozen matches.

Last night’s third period, in which the Blueshirts played with fortitude and a sense of purpose in dominating Winnipeg only to be undone in large measure by a shockingly soft fourth goal allowed by Henrik Lundqvist, could provide a platform for this team that is seeking equilibrium.

“I think that a desperate third period like we played helps us to develop the belief we need in ourselves,” said Marian Gaborik, who has scored only one goal in the last eight games. “We have to take the good out of this and not get down.”

The Rangers, however, did go down 2-0 and 3-1 in a second period during which the Jets seized on home team mistakes. The Blueshirts fell behind despite a memorable shift by Callahan 4:45 into the second on which the captain — who finished the match with a goal, seven shots, 11 attempts, five hits and two blocks — broke his stick yet blocked a pair of shots by flinging himself in front of a pair of Zach Bogosian drives from the left point.

“I was just trying to block shots,” Callahan said. “It had nothing to do with trying to spark a team. It’s just the way we have to play and what you have to do to get wins.”

John Tortorella moved Carl Hagelin off Derek Stepan’s wing for the first time in 13 games and onto the flank with Brad Richards, flipping spots with Taylor Pyatt. The Stepan-Pyatt-Callahan unit that was the Rangers’ best brought the team back within 3-2 in the third on a Pyatt deflection.

But 20 seconds later, Lundqvist surrendered a right wing softie to Evander Kane and thus made the hill a bit too steep to climb, despite Anton Stralman’s score 53 seconds later at 10:30 that was followed by flurries of chances the rest of the way.

“I’ve gone over it a couple of times and I’ve tried to find out a reason for why, but it doesn’t matter,” Lundqvist said. “I need to stop it,”

Now the Rangers need to find confidence. It won’t come easy.

“There is definitely a lot there to build on, but It does take an effort to be positive because we’re losing, “Callahan said. “It’s hard to be positive off of a loss, but we have to.